HANGZHOU SILAN MICROELECTRONICS CO., LTD.

HANGZHOU SILAN MICROELECTRONICS CO., LTD. Patent applications

Patent application number

Title

Published

20140092648

SWITCH-MODE POWER SUPPLY CONTROL APPARATUS AND FLYBACK SWITCH-MODE POWER SUPPLY INCLUDING THE CONTROL APPARATUS - The present invention discloses a switch-mode power supply control apparatus comprising a PWM controller for outputting a driving signal and a short-circuit protection module coupled to a detection terminal. The detection terminal receives a zero-crossing detection voltage. If the time that the detection voltage input to the detection terminal is lower than a first reference voltage exceeds a predetermined time period, the short-circuit protection module determines that a short-circuit abnormal situation occurs, the short-circuit protection module outputs a short-circuit signal to the PWM controller, and the driving signal output by the PWM controller becomes a turn-off signal. If the short-circuit protection module does not detect the short-circuit abnormal situation, the PWM controller operates normally. The present invention further discloses a flyback switch-mode power supply comprising the switch-mode power supply control apparatus. The flyback switch-mode power supply has a low power consumption when a short-circuit protection is taking place. Also, the transformer will not be saturated, which may otherwise lead to the damage of the power transistor. Further, the present invention makes it easier to test the short-circuit performance.

04-03-2014

20130057173

PRIMARY-SIDE CONTROLLED SWITCH-MODE POWER SUPPLY CONTROLLER FOR DRIVING LED WITH CONSTANT CURRENT AND METHOD THEREOF - The present invention discloses a primary-side controlled switch-mode power supply controller for driving LED with constant current and method thereof as well as an apparatus for controlling switch-mode power supply having the switch-mode power supply controller. The switch-mode power supply controller includes an input dimming phase detection circuit, a multiplier, a turn-on signal control circuit, a zero-crossing detection circuit, a comparator, a trigger and a driving circuit. The circuit controls to drive LED with constant current by means of a primary-side controlled method. The circuit realizes the triac dimming function, ensures a constant output current regardless of a high voltage or a low voltage, and obtains a high power factor. The direct use of the isolation transformer improves the safety of the circuit, and simplifies the peripheral circuit, thereby reducing the cost of the circuit and minimizing the size of the PCB layout, which is favorable in minimizing the product.

03-07-2013

20130039098

OFFLINE AC-DC CONTROLLER CIRCUIT AND A CONVERTER COMPRISING THE SAME - An offline AC-DC converter circuits including an overvoltage detection module, a current limiting module, a PWM module and a switch control module coupled to the above modules. The overvoltage detection module, the current limiting module and the PWM module share a common input terminal. The sampled current signal and the sampled voltage signal are provided at the common input terminal by way of time-division multiplexing. With the time-multiplexed terminal, overvoltage detection for the output voltage is performed during the period when the power transistor is cut off and a current through the power transistor is detected during the period when the power transistor conducts. The two signals are input by way of time-division multiplexing, which are not affected by each other. Accordingly, overvoltage in the output voltage can be precisely detected without additional terminals, and thus the overvoltage can be controlled.

02-14-2013

20120163042

CIRCUIT AND METHOD OF FREQUENCY JITTER, AND APPLICATION THEREOF IN SWITCHED-MODE POWER SUPPLY (SMPS) - The present invention is to provide a frequency jitter circuit and a method for generating frequency jitter. The frequency jitter circuit, comprising: an oscillating circuit, configured to generate an oscillating frequency output signal; a decoding circuit, configured to be controlled by said oscillating frequency output signal for generating several pulse output signals; a delay circuit, through which said oscillating frequency output signal is passed for generating a frequency jitter output signal that is delayed a period of time compared to said oscillating frequency output signal. Application of the invention into switched-mode power supply might reduce EMI average noise in the switched-mode power supply, and smooth energy spectrum density.

06-28-2012

20120155121

SWITCH-MODE POWER SUPPLY AND APPARATUS FOR COMPENSATING INDUCTOR CURRENT PEAK - A switch-mode power supply (SMPS) is provided. When the switch power of the SMPS turns on, the inductor current of the SMPS may flow through an inductor current sensing circuit which then provides a sensing voltage. An apparatus for compensating the inductor current peak receives a reference voltage and the sensing voltage as inputs and outputs a compensation voltage. The compensation voltage is combined with the reference voltage and/or the sensing voltage and is provided to a first comparator. The result keep